Category: Insights

The importance of managing manure on-farm 

Posted on January 11, 2024 by - Insights, News

Written by Becky Willson, Business Development & Technical Director.

Manure is a fantastic on-farm resource. This is because it can deliver a source of nutrients that can be used to grow crops, as well as enhancing soil biological activity, feeding the soil microbes and helping provide a steady supply of organic matter. This can ensure that soils are in the best condition structurally, chemically and biologically. Manure is one of the most important resources that is produced on-farm, and should be valued rather than seen as a waste product. 

A key way to be able to reduce reliance on fertilisers is to develop efficient and effective strategies for managing nutrients and manures on-farm. 

Nutrient management planning

Managing nutrients in a systematic way through planning is a vital aspect of sustainable farming. It is a ‘win-win’ practice which generates advantages across economic and environmental parameters, and allows for the creation of a sustainable agricultural system which is resilient to climatic and economic change. 

Nutrient management planning facilitates optimal use of nutrients from all available sources. Matching inputs of nutrients (from fertilisers and organic manures) to the demand from the crop will allow for an optimal yield, minimise the use of nutrients (which saves costs) and minimises the risk of losses to the environment from nutrients.  

Slurries and solid manures are valuable fertilisers but may also be potential sources of pollution. Within increasing economic and environmental pressures on farm businesses, it makes sense to exploit the fertiliser value of manures while taking action to prevent pollution. 

Most farm assurance schemes require a manure management plan to be completed as part of the certification process. However even without the compulsion of a scheme, having a plan which marks out any environmental features, watercourses, sloping fields which may cause run off and any areas will be a useful resource to consult before applying manures.  

The need for effective manure management

The most effective way of dealing with livestock manures is to apply them at appropriate rates to agricultural land for the benefits of soil and crops. Getting manure management right allows for sustainable use of resources which provides economic savings and reduces the amount of artificial fertiliser that is required. Manures, when stored and applied correctly have fantastic benefits in building resilience within your farming system, cutting costs and lowering your carbon footprint, however if they are applied in too high a quantity or at the wrong time of year then they are an environmental risk. So it is the job of farmers to maximise the benefits that can arise and minimise the risks.

Nutrient management planning to mitigate greenhouse gas emissions

Nitrogen emissions to the air from farms include greenhouse gases, the most potent of which is nitrous oxide. Nitrous oxide is one of the biggest contributions that agriculture makes to climate change. Soil nitrous oxide emissions originate from three sources, soil microorganism activity (55%), organic manure applications (18%) and Nitrogen fertiliser applications, (27%). As such, careful management that maximises the efficiency of any fertiliser applied, takes account soil and climate conditions, and uses the nutrients within manures for crop growth will help to reduce the amount of nitrous oxide lost. 

Nutrient and manure management planning will also help reduce ammonia emissions. While ammonia isn’t a greenhouse gas, it negatively impacts air quality and human health. The amount of ammonia which is lost depends on a variety of factors including manure type, the method and timing of applications, soil pH, the weather conditions at spreading, the soil moisture content and how the manure is stored. As such there are a variety of mitigation options available that are made easy by planning how manure is managed to reduce these risks. 

Soil Testing

Although not always considered as linked to nutrient management planning, monitoring and controlling the pH of soils on-farm is the first step toward good nutrient management. If soil pH is not correct then any nutrients that are applied through fertiliser or manure applications will not be available to the crop and may be lost from the soil incurring costs, reduced yields and pollution issues. 

Effective use of manures – Storage

Having sufficient slurry or manure storage means that effective nutrient management planning is much easier. With sufficient storage capacity, slurries and manures can be applied at the optimal time for plant growth and crop uptake, as well as being applied when the soil and field conditions are right and damage (including compaction and run off) is minimised.  However for some farmers who don’t have enough storage, slurry has to be spread in less than ideal conditions, when there is little crop growth and nutrient uptake. It is in these situations where environmental losses can be the highest. 

Thankfully there are ways that storage can be optimised. This can include minimising the amount of rainfall that is able to enter the store. Rainfall can dilute the nutrient content of the slurry but also costs more in manure application – more water is held within the slurry leading to a higher volume to be spread. Mending guttering, diverting clean water away from stores and covering yards to minimise the amount of water that is entering the store are all low cost ways to help maintain the nutritional value of the manure and also reduce costs. Covering stores is also an option and there are various cover options that are available depending on the store type and design. Floating covers will also reduce the amount of ammonia which is released into the atmosphere which has air quality benefits. 

With solid manure it is important to consider the siting of field heaps and managing the heap to ensure that Nitrate leaching is minimised. Composting of FYM will provide a more stable and uniform material which will have benefits for soil biology, but will not provide such a high readily available Nitrogen source as fresh manure. 

Effective use of manures – Application 

Ensuring that manures are applied at the right rate and the right time is the most important step to reducing environmental risk and improving economic performance of the farm.  The method of application can affect the amount of nitrogen that is available to the crop. Although the total nitrogen content within the manure cannot be altered by the method of application, the proportion of the nitrogen that is available to the growing crops is improved by using low trajectory machinery.

Spreader technology has developed over recent years so that now there are numerous options available for spreading slurry (where losses are potentially higher). Broadcast spreaders will waste nutrients, but this can be minimised by using injection or band spreaders which put the slurry directly on the soil surface or into a narrow slot. For solid manures, the evenness of spreading is far improved by using a rear discharge spreader. If manure or slurry is to be incorporated, ensuring that it is done quickly after application and not just left on the surface where the nutrients may well be lost is important.

Optimising the use of manures and slurries on-farm will provide benefits through improving profitability, resilience and soil health. For more information on manures and nutrient management planning please visit the FCT toolkit pages to access a range of resources.  

A Day in the Life of…James Pitman, Calculator Development Officer

Posted on April 17, 2024 by - Insights, News

The day-to-day responsibilities of a carbon calculator development officer are a little more sedentary than those of our farmers or my advisory colleagues, but the intricacies of the job mean my life is far from mundane.

My primary objective is to continuously work on refining and enhancing our carbon calculator, ensuring it remains an accurate, trusted, and invaluable tool for UK farmers. 

A significant portion of my time is dedicated to the core emissions factors that underpin the calculator. This can mean verifying or updating our existing factors, researching new factors, or addressing the requests from users and advisors about factors they want on the calculator. In the last couple months I have been working closely on the Version 1.6.0 update to the calculator, which required a comprehensive review of all the emissions factors we use. This was a formidable task, and I have spent countless hours scouring through spreadsheets, deep in research papers, and having lively video calls with the team and our software developers. For all this work we have been able to add great functionality to the calculator and made really exciting plans for what is in the pipeline (no spoilers!), so the toil has paid off and I am very satisfied with the extent of new data and functionality we have been able to add in such a short window of time.

Since starting with FCT in December 2023, I have also been fortunate enough to help in the creation of the Equine Carbon Calculator, an industry-leading initiative aimed at quantifying emissions from the equine sector. During this development process you could have found me doing a myriad of tasks, from researching how the emissions would vary between different horse breeds, to calculating the materials needed for stable buildings and their embedded emissions, or beta-testing the new website and calculator. The opportunity to be involved with the Equine Carbon Calculator was fantastic and I have been thrilled to see how many reports have been built in it since it went live in March 2024.

The enthusiasm and passion FCT and its community have for sustainable agriculture is inspiring, and as a new member of the company I have never felt so welcome and excited about a new job. I hope that my work with the calculator team will create an efficient and effective tool for you all, and with that I am going to dive back into the research papers!

A Day in the Life of… Liz Bowles, Chief Executive

Posted on January 11, 2024 by - Insights, News

Being Chief Exec of the Farm Carbon Toolkit is a privilege. I have a team of committed, enthusiastic and supremely knowledgeable people working with me who are dedicated to supporting farmers to understand their farm carbon footprint and to reduce greenhouse gas emissions and increase carbon sequestration, whilst maintaining thriving, biodiverse businesses.  

We are a relatively small organisation, but I always love it when people tell me that they keep coming across the team as this means we are being noticed and, even more importantly, that people like what we are doing. Last week was just such an example. We were involved in a number of sessions at the Oxford Farming Conference including showcasing Farm Net Zero Cornwall and the great strides farmers involved in the group are making towards Net Zero. We also featured in the premiere of the film “Six Inches of Soil”  and were mentioned by a number of other speakers at the conference whom we work with.

There is no such thing as a typical day for me.

I do start off with a list of what I would like to get done during the day and highlight the tasks which are important/ urgent, but then things happen, such as people making contact with me to discuss exciting new activities with which we could get involved. It is just about impossible to know which opportunities are the best to take forward from the great number which come our way every day, but my watch word is to pursue working with like-minded organisations whose first instinct is to think about what they can do to support reducing the greenhouse gas emissions from agriculture and who, like us, believe that farmers are supremely well-placed to remove carbon from the atmosphere through how they farm.

Over the last few months I have been developing relationships with other popular Carbon Calculators to enable us to work together where possible to harmonise Calculator methodologies, so that farmers’ Carbon Calculator results will be more comparable in future. This, I believe, will increase the uptake of their use. We know that the requirement to provide information on farm emissions and removals will increase over time and we are committed to continually improving our Calculator so that farmers who are taking action to reduce their carbon footprint can see this fully reflected in their reporting. We are also committed to providing our Calculator directly to farmers for free.

A Day in the Life of… Emma Adams, Senior Farm Carbon and Soils Advisor

Posted on March 20, 2024 by - Insights, News

This January I was very fortunate to attend the 27th Challenge in Rural Leadership course, run by the Worshipful Company of Farmers and Duchy College, with my place supported by the Henry Plumb Foundation and FCT. Throughout the course, I was able to work alongside other industry leaders, understand why they succeed and practically improve my expertise. However, it was also very clear that leadership is not inherited through attaining a particular job title or level of responsibility. There were many insightful and poignant moments from the course, but one of my favourites was from Mary Quicke, of Quicke’s Cheese in Devon – “No one has ‘Spent a long time in the office’ on their grave”. So with that, what am I getting up to?

FCT operates on an incredibly diverse scale, whereby we have the great privilege of working with farmers and growers across all sectors and corners of the UK and beyond. This is brilliant and makes each day highly varied but does mean that many lists are made in a day of the tasks arising. Today for example started by packaging up soil samples heading for analysis from a wonderful project we have up in the Lake District (thank you West Cumbria Rivers Trust and the lovely farmers involved) looking at baselining the soil health and carbon status of the farms. This quickly proceeded into finalising proposals for upcoming projects with Lamb Weston and First Milk – two brilliant companies who although operating in different sectors (potatoes and milk production) are both passionate about producing sustainable food to the highest standard.

This week I am also participating in some filming for a project we have recently launched with the Royal Countryside Fund titled ‘Savings in Soil’. It is a brilliant project looking to help farmers measure and manage their grassland’s soil health to benefit future farm resilience. As ever, soil underpins a healthy and productive grassland system, capable of producing healthy pastures and livestock, which in turn supports a profitable farming system. 

I am very lucky to facilitate the Soil Farmer of the Year competition, as such the day also bought liaison for this year’s application process. The competition aims to find and champion UK farmers who are engaged with and managing their soils to the benefit of their farming system and the wider environment. We are supported again this year by Hutchinsons and Cotswold Seeds, so again an opportunity to say thank you to their teams! 

So, despite a little bit of time in the office today – we have managed to work with a huge variety of topics and geographies, continuing to assist the fabulous farmers, communities and industries of UK agriculture.

A Day in the Life of… Becky Willson, Technical Director

Posted on February 13, 2024 by - Insights, News

One of the wonderful things about working for FCT is that no two days are the same. I am incredibly lucky that I get to work with such a brilliant group of colleagues and some fantastic farmers.  Everyone brings new skills, knowledge and interests, which allow us to learn from each other and share ideas which is really rewarding. 

This week has been an interesting week. I am currently delivering a new course which is being run by the University of Cumbria entitled Upland Farming for Net Zero. We have a great cohort of 15 students who are either directly farming or involved in supporting our upland farmers in the South West. This week, we have had online sessions focussing on storing more carbon in upland environments and measuring emissions from livestock, alongside a farm visit on Monday to discuss what it all means in practice.  What’s great about this course is that it also feeds into a project we are just completing, which has built a version of the carbon calculator specifically for upland farmers to be able to take account of carbon on-commons, which is a welcome step forward. 

I have also run a couple of training sessions for groups within the Royal Countryside Fund, providing an introduction to managing carbon on the farm. Although I do a lot of these types of talks, they never get boring as each session yields a different set of questions. What I get most enjoyment from is the interaction with the farmers and helping them to see how what I’m saying could be put into practice. It’s so rewarding to be able to help in some small way, even if it is just to help empower them to feel part of delivering the solutions. 

Alongside talks, I have been finishing off a couple of reports for projects that are coming to an end: a dairy footprinting project combining farm footprints for the supplier farms with the operational footprint of the processing site, and writing some factsheets for farmers around the importance of managing manures and the opportunities with cultivation. There is always more to do and new projects and ideas to explore.

A Day in the Life of… Dr Hannah Jones, Farm Carbon and Soil Advisor

Posted on December 7, 2023 by - Insights, News

 No day at work is remotely similar, every field is different, and each farm is unique. However, there are common questions that are raised during a carbon audit, farm event or trial set-up. It is these questions which motivate me to find how we can support farmers’ to build the resilience of their businesses and in so doing reduce their carbon footprint.

Years ago, I worked with one of the UK’s leading agro-ecologist, Professor Martin Wolfe who greatly inspired me. Central to Martin’s teachings was the need to understand the effect of environment on the expression of the genetics of an organism. In the context of the farm, it is the effect of that individual farm environment and the management which alters crop or animal performance. These on-farm trials can have quite different outcomes from average values from national data sets.

In this context, it is the trials on-farm which provide the information for individual farmers or the associated farmer clusters. These trials, which might be just a single pass of a different seed mix or replicated trials over multiple farms, that provide the information to change a farming practice. In addition, and most importantly, these small trials and discussion groups reduce the risk associated with a change in practice and allows collaboration in terms of machinery or technological know-how.

The Farm Net Zero project , funded by the National Lottery, is focused on working with a farm community in Cornwall. It is this funding that has allowed me, as part of a wider consortium, to work with groups of farmers to address common areas of interest. The project is in its third year, and the work continually inspires me because of the evolving dialogue, increases in soil health, reducing emissions and a community network that gains increasing strength.

It is hard for anyone to make a change, but it is particularly challenging for complex businesses that are vulnerable to variability in climate, biological risks from pests and diseases, as well as changing market and policy forces. As part of a community, my favourite working days are those spent with groups of like-minded farmers focused on addressing a common challenge and reducing risks associated with changing to a more sustainable practice. I imagine Martin would approve.

How do we measure peatland?

Posted on December 7, 2023 by - Insights, News

Understanding the carbon dynamics of peatland is a complicated process that is ever-changing for land managers and farmers. Historically, peat soils and habitats have been understood as a carbon store, with peat itself being of extremely high carbon content. However, in the process of carbon footprinting it is required to understand all greenhouse gases associated with peatland (carbon dioxide, methane and nitrous oxide) and the additional storage of carbon into these soils, a process known as sequestration. 

Sequestration is the process of capturing carbon from the air and storing it within the land, through the process of photosynthesis. Within peatland soils there are additional layers of complexity when thinking of carbon storage. The waterlogged conditions of peat soils allow decomposing plants to accumulate, storing the carbon in the form of peat; this means that not only is carbon captured and stored via photosynthesis, but that there are direct carbon additions from the plant structures themselves. 

Consequently, measuring peatland within the Farm Carbon Calculator or any carbon calculator can be complex – knowledge in the scientific community alongside methods of accounting are rapidly developing. However, the following methods can be used:

  • Direct Measurement: soil sampling the peatland soil to understand the carbon content (Soil Organic Matter or Soil Organic Carbon testing) provides a figure of the carbon stock within an area. Carbon stock is the quantity of soil contained within a soil at the time of measurement and is calculated in combination with a Bulk Density sample. To understand if your peatland is sequestering carbon (capturing more, additional carbon) this sampling needs to be repeated to understand whether the figure measured in the first instance is increasing or decreasing. Soil sampling can be conducted annually, but there is often concern around carbon flux so the Farm Carbon Toolkit would usually recommend sampling every 3-5 years. More can be found out about how to sample soil in our free online guide to monitoring soil carbon on the FCT website here.
  • Modelled Measurement: if however direct measurement is unsuitable or you would like a faster indication of the carbon dynamics of your peatland soil you can use modelled figures embedded within the Farm Carbon Calculator. Using data from the Peatland Carbon Code 2.0 there is the ability to account for peatland areas of the landscape through selecting the type of peat you have and the area (hectares). The calculator will then provide a modelled suggestion of the likely dynamics of the different greenhouse gases associated with the different peat classifications. 

The Fellfoot Forward Project: A Case Study

Posted on December 7, 2023 by - Insights, News

In December 2021, five farmers from the Fellfoot Forward Landscape Partnership participated in a carbon footprinting project in association with the Farm Carbon Toolkit. Based in proximity to the North Pennines AONB these five upland businesses demonstrated how livestock farming can work in conjunction with the wider landscape to produce quality food whilst providing environmental services such as water and air quality alongside carbon capture and storage. 

A carbon footprint, or carbon balance, is the measure of the total emissions and total sequestration associated with a particular business or product. For this project, the whole farm was measured to include all of the enterprises included within a farming business. When we discuss ‘carbon’ we are referring to ‘CO2e’ or ‘carbon dioxide equivalent’ which is a measure of the three main greenhouse gases carbon dioxide, nitrous oxide and methane. Different greenhouse gases have different dynamics within the atmosphere, consequently having higher or lower warming potentials and thus potency as a contributor to climate change. Therefore, ‘carbon’ as a term encapsulates all three of these gases under one metric so we can compare items such as fuel alongside the biological systems seen in livestock like for like.   

To produce a carbon footprint the farmers were asked to collect a variety of data associated with their business, including items such as fuel and water usage, livestock numbers and quantity of materials used for activities like silage wrapping or maintenance. Alongside these figures, it was also important to record the ‘natural capital’ of each farm holding – the resources found in the farmed environment which are managed as part of the business but provide wider ecosystem services and value – such as areas of woodland, length of hedgerows, soil organic matter and specific habitats such as floristically enhanced margins or wetlands. When all of these details had been recorded, the data was entered into the Farm Carbon Calculator to produce a carbon footprint detailing the balance of emissions and sequestration found at each farming business. 

For the farms included in the project action plans were created to highlight where emission savings can be made or sequestration opportunities maximised. All of the farms within the project were found to be likely to be able to reach a Net Zero, if not already in this position. A large factor on many farms to reach this target is proper accounting of carbon held within the soil as organic matter. For the Fellfoot Farmers who are in majority grassland systems, livestock can be utilised as a tool to increase organic matter in soils – either through grazing systems and the capture of sunlight to be stored as carbon, or through the return of manure to pasture for nutrient cycling. To fully account for the potential sequestration of carbon through the building of organic matter in soils regular testing should be conducted to measure and monitor the levels found in soils. If, like on many farms there has been no prior soil organic matter testing the best advice would be to select three or four key fields within the farmed area which are representative of the systems within the business. For example, if the farm was in a grass-based system, a field which is usually cut for silage, one only grazed and a traditional low-input or hay meadow would demonstrate potential underlying trends in organic matter across the landscape. Equally, if there is a range of soil types or diversity of land use on a single farm it would be perhaps useful to test fields representative of these features to better understand trends and consequently the best management approach to conserve existing carbon and build stocks in the future. As ever, when testing soils aim to minimise external variation by ensuring consistency in the laboratory used and the time of year when sampling.   

The project with the Fellfoot Forward farmers demonstrated the variety of approaches to upland livestock farming, from the number or type of stock to the management required to protect and enhance vulnerable habitats within their farmed area. Some of the farms included in the project had areas of peatland within their management, using cattle or sheep to maintain and conserve the landscape in association with government or local schemes to the benefit of the wildlife and ecology found there. Peatlands are a vast store of carbon and consequently, the condition of this landscape could greatly impact upon the land managers responsible for its status. More information is required to fully understand the dynamics of peat and how farmers can measure and monitor this landscape for not only carbon footprinting processes but also for generations to come. 

Carbon footprinting is a process that can be repeated on an annual basis, used as a monitoring tool for both the emissions and sequestration of a farming business but also to understand changes in management approach. There is a general underlying correlation between high carbon and high cost on many farms, with items such as fertiliser and blended livestock feed being both expensive and also a comparatively larger contributor of emissions. Therefore, conducting a carbon footprint not only has benefits towards understanding the environmental impact of a business but also can be used as a tool for resource optimisation and economic efficiency. 

Key findings

  • Conduct organic matter testing to understand the current carbon held within soils. Aim to repeat this testing every 3-5 years to understand whether your soils are sequestering (increasing in organic matter) or emitting (decreasing in organic matter) carbon. 
  • Account for things you are already doing such as hedge or tree planting that are under existing or future schemes.
  • Accept that you may not have all the data, aim to create a baseline from which you can repeat the process in future years and account for more information with more experience, time or understanding.
  • Identify ‘hotspots’ where emissions are highest. Except for cropping or livestock, are there particular items or categories which contribute a larger proportion of emissions than others, is there potential for reduction in these areas?

A day in the life of… Sam Smith – General Manager

Posted on September 16, 2023 by - Insights

I’m the General Manager at the Farm Carbon Toolkit (FCT), a role that oversees our operations. This includes finances, human resources, and communications – and working to make sure we have good systems and processes in place so that people have what they need to succeed in their work. 

As much as I can, I also support the development of our strategy and new projects – managing some existing ones too, related to our Farm Carbon Calculator.

On the side, I am completing a Nuffield Farming Scholarship which I was so grateful to receive in 2020, the year Covid turned our lives upside down. That year, my wife and I also moved to Edinburgh and had a baby daughter, which has been the most joyful, life-changing experience. Although it hasn’t been particularly compatible with doing a travel scholarship, somehow, last week, I finished the Executive Summary (here if you are interested) and I’m now getting ready to present at the annual Nuffield conference in November. 

I’m feeling nervous about this presentation, especially as I’m not a farmer and my operations-heavy role in recent years has left me feeling a bit disconnected from the trends. Yet, I can only do my best. In August, I had some incredible travels in the USA and last Summer, across Europe – engaging with many brilliant farmers and food businesses. I’m very grateful for the support and flexibility from colleagues as I have undertaken this. 

I fell into this role slightly by accident. My past roles have mostly not been operational, but I developed some of these skills when managing Sutton Community Farm, a small community business on the edges of London. After this role, feeling curious about the bigger food system, I worked at Forum for the Future, engaging with various major food brands and retailers. FCT is a happy medium, a challenging role that combines various skills and experiences from the past, with a passion for sustainable farming, within an organisation that’s hands-on and practical in their approach. I love our purpose, values and approach. But most of all, I’m in awe of my colleagues’ knowledge and experience in sustainable farming. I learn so much from being around them and it’s my wish to be able to join them out in the field more. 

Photos from recent travels in the USA. Above: Hickory Nut Gap Farm in North Carolina. Top image: Sam volunteering at Soul Fire Farm in Grafton, New York.

I relentlessly think about how we can improve our workplace so that people have what they need and don’t get bogged down in bad or frustrating systems. I’m keen that we also cultivate healthy working practices and live up to our shared values. This can be more challenging as a remote organisation, requiring extra effort to keep in touch and care for each other. 

It’s been quite an adventure these last few years. We’re growing steadily and working to expand our systems to fit this growth. Even though FCT is over 10 years old, it wasn’t until the end of 2020 when things started to really take off. When I started in August 2020, our only other staff member was Becky Willson on secondment from Duchy College, alongside much voluntary effort from Directors. Today, we have 14 staff with 3 more about to start. I’m so proud of this journey and feel very excited to see where things go from here. 

Read more about Sam and the rest of the team here.

Risky Crops

Posted on September 15, 2023 by - Insights

Certain crops (potatoes, sugar beet, maize, field vegetables) within a wider arable rotation pose increased risk of soil loss or degradation. Often described as ‘risky’ these crops may require additional management to ensure that field conditions are favourable and that there is no long-term disruption to soil functionality or structure. 

Aside from the impact upon soil, ‘risky crops’ are often those which have a potentially higher financial burden through the obstacles of production. Rising input costs, labour shortages and ever increasing inflation presents additional challenges to high-risk, high-reward crops. These two elements (soil management and economics) are additionally impacted through the changing climate with record temperatures and rainfall events.

Root crops, maize and field vegetables are often at high risk for soil degradation. The likely drastic requirements for cultivation during seedbed preparation is a vast source of emissions through direct carbon losses from soil alongside the burning of fossil fuels from machinery. Cultivating soils and the subsequent disturbance allows for greater oxidation of the soil profile, therefore promoting the fast metabolism of aerobic species of microorganisms which utilise the ‘active’ pool of soil organic matter for respiration, consequently releasing CO2 as a by-product. Furthermore, cultivation of soil which reduces the stability of the soil structure can also be at risk of direct losses of carbon bound to soil aggregates through processes such as erosion either through wind-blow, run-off or direct soil loss.  Therefore, depending upon a number of factors such as previous cropping, soil type, intensity of cultivation and moisture content, cultivated soil will lose soil organic matter at differing rates. Where land is under continual cultivation, as is much of UK arable land, reducing the frequency, depth and intensity of cultivations will reduce this soil carbon loss alongside providing alternative carbon sources as feedstock for microorganisms when cultivation is required. 

Changing the crop establishment system to reduce the frequency and intensity of cultivations will provide an immediate reduction in farm greenhouse gas emissions. Increasing organic carbon within the soil requires the building of soil organic matter through methods such as diversifying crop rotation, reducing tillage (frequency and depth) and utilising cover cropping to maintain a living root. 

Long-term rotational planning can increase the resilience of soil, using previous and subsequent cropping and management choices to minimise the impact of risky crops. To reduce the ‘risk’ of risky crops soil protection is central. Ensuring that soils are covered throughout the rotation and contain a living root for as high proportion as possible helps guard the soil from physical degradation from climatic events. Therefore, consider growing a cover crop before spring planting to scavenge nutrients over the winter period and condition soils, alongside aiming to re-plant a cover as soon as the risky crop is harvested to avoid long over-winter periods of soil erosion. Maximising the inherent soil structure and functionality throughout the rotation creates a more resilient baseline where the stresses of high cultivation, inputs and exposure to the elements occurs in high risk crops.

In grassland systems herbal leys, diverse swards and a rotational or mob grazing platform provides an excellent starting point for soils before a high-risk crop or to repair potential damage. Likewise a diverse arable rotation which incorporates cover, inter, companion or catch-cropping to protect the soil surface and provide additional rooting architecture will be a huge benefit; tired land, used to high input use, heavy cultivation and monoculture systems will be less resilient to stress (environmental, mechanical etc) than a healthy vibrant soil. 

A healthy soil is likely to provide better economic returns – with processes such as fertility, water infiltration, gas exchange, rooting capacity and nutrient availability all benefited by a well structured, high quality soil. Soil organic matter can often indicate the health of a functional mineral soil, with the higher the percentage content normally suggesting the best quality. Understanding how soil organic matter can be lost during high risk cropping processes (discussed earlier) can help to mitigate and safeguard it within the rotation. Losing soil organic matter continuously depletes the soil fertility and consequently the likely economic potential of that land. 

This blog was written by Emma Adams, one of our Farm Carbon and Soils Advisors, to read about our team head here.

More information:

For further information on species selection of cover crops and the results of the Farm Net Zero trails please see the resources below: